Potential colitis drug may need more studies: FDA

WASHINGTON (Reuters) - Abbott Laboratories Inc may need to conduct additional trials of Humira to prove the blockbuster drug helps patients with ulcerative colitis, U.S. drug reviewers said on Friday.

Staff from the U.S. Food and Drug Administration questioned whether Humira had a real benefit for people with the inflammatory bowel disease who had already tried other treatments. The FDA review comes ahead of an advisory panel, which will vote on whether to recommend the drug on Tuesday.

Humira, one of the world's top-selling drugs with projected sales of $9 billion this year, is already approved for six conditions, including arthritis. Abbott hopes to expand its use to people with moderate to severe ulcerative colitis, a chronic disease that causes ulcers in the colon and affects about 700,000 Americans.

The FDA rejected Abbott's first application for ulcerative colitis last November, saying results from clinical trials did not conclusively show the drug helped stop the symptoms of the disease, which include diarrhea, rectal bleeding, incontinence, abdominal pain, fever, fatigue and weight loss.

The reviewers on Friday said Abbott had submitted more analyses of the data in a second application, but they were "of questionable value."

As Humira already has known safety risks that include serious infections, the FDA staff said it was unclear if the drug's modest benefits justify giving it to patients instead of other approved drugs, such as Johnson & Johnson's Remicade.

"Additional evidence could help support the evaluation of the benefit-risk assessment for a Humira (ulcerative colitis) indication," the FDA staff said in documents posted online on Friday. They said the company could consider increasing the dose, or proving that people who failed other drugs had more success with Humira.